Five 0.1 hectares of test ponds were stocked with the mean body weight1.5g of hard clam larvae. Each pond had 100,000 clam (culture density of 1 million clam/ha). The masking rate experiment was carried out. After 6 months of breeding experiment, the results were found that The change of water temperature in each ponds under strong sunlight during the months shows that the higher the shielding rate in May to August, the more the water temperature drops. From the total ammonianitrogen concentration in the pond water, it can be seen that the deaths of the clams in each of the ponds occurred in June and September. During the high temperature period from May to August, the growth of the control group (S-0 test cell) was lower than that of the S-40A test pond with a 40% shielding rate, indicating that moderate shielding during high water temperature can cause the water temperature to drop. And making a good growth environment for clam. The average weight of the control group (S0) was gradually better than that of the other 4 groups after September. The average body weight of the test pool, S-0 >S-40A >S-70, showed that the higher the masking rate, the worse the growth. From the results of this test, it is found that in the case of 70% of the S-0 production, the output of other test ponds meets the requirements except for the S-40C test pond.